<the existing model>
Wondering why Sony's redesigned PSP costs $249, $80 more than the existing model? You're not the only one. During an interview on Bonus Round, noted games industry analyst Michael Pachter accused Sony of "ripping off the consumer" and asserted that the PSP Go will actually cost less to make than the current machine.

<the current model>
The new Prius, due to debut in Japan in mid-May, will have a 1.8-liter engine instead of the 1.5-liter engine driving the current model.

Are "the curremt model" and "the existing model" interchangeable?